非金属桥塞镶齿卡瓦的有限元分析及优化

Finite Element Analysis of Inserted Tooth Slips of Non-metallic Bridge Plug and Optimization

运用Abaqus有限元软件对一种新型非金属桥塞镶齿卡瓦的锚定过程进行弹塑性接触有限元分析,获得了锚定时卡瓦牙及套管的弹塑性Mises应力分布、接触应力分布和接触力分布规律。分析结果表明,套管内壁所受卡瓦牙接触应力和接触力从卡瓦中部沿周向逐渐减小;同时,与卡瓦槽接触的各卡瓦牙底端最大Mises应力均接近于同套管接触的顶端应力值,卡瓦牙应力集中明显。将卡瓦牙和卡瓦结构优化设计后,避免了局部应力集中。卡瓦与套管之间接触应力和接触力的略微增大,也让卡瓦与套管的锚定更稳固。

The structure of non-metallic bridge plug inserted tooth slips is complex, so its theoretical analysis is troublesome. The Abaqus finite element software was applied to conduct an elastoplastic contact finite element analy- sis of the anchoring process of a new type of non-metallic bridge plug inserted tooth slips. The laws of elastoplastic Mises stress distribution, contact stress distribution and contact force distribution of slip element and casing in an- choring were obtained. The analysis shows that the contact stress and contact force of slip element on the inner wall of casing gradually decrease circumferentially from the middle of slips. Meanwhile, the maximum Mises stress of the bottom end of slip elements in contact with slip groove is approximate to the stress value of the top end in contact with casing. The stress concentration of slip elements is remarkable. After optimization of slip elements and slip structure, the local stress concentration is avoided. The contact stress and contact force between slips and casing in- crease slightly. As a result, the anchoring of slips and casing is more stable.